Meteor activity produces glowing night clouds seen over northern USA and Europe

High above Earth, glowing clouds of frosted meteor smoke are spilling over populated areas of the USA and Europe.

“Last night, for the first time this summer, noctilucent clouds stretched across our whole sky,” reports Danish observer Pernille Fjeldgaard Jensen. “Some of the clouds looked like silver corkscrews spiraling their long arms towards us.”

“It was a fantastic display,” says Jensen, who took this picture from Denmark’s Lille Vildmose Wild Life Park.

Noctilucent clouds (NLCs) form when summertime wisps of water vapor rise to the top of Earth’s atmosphere and crystallize around specks of meteor smoke. Mesospheric winds gather the resulting ice crystals into clouds that float more than 80 km high. They can be seen long after sunset as they ripple and swirl across the night sky.

Observers in Europe have been seeing these clouds for more than a month. On July 4th, bright NLCs finally visited the continental USA. Dustin Guy saw the silvery forms spreading over Seattle:

“It was one of the most vivid noctilucent cloud displays I’ve seen in years,” says Guy.

July is often the best month for NLCs with sightings in previous years as far south as Utah and Colorado. This week’s display in Washington state means US observers may soon be able to join Europeans in their regular contributions to the NLC photo gallery.

Observing tips: Look west 30 to 60 minutes after sunset when the sun has dipped well below the horizon. If you see luminous blue-white tendrils spreading across the sky, you may have spotted a noctilucent cloud.

Observers of noctilucent clouds (NLCs) often describe their color as “electric blue.” This high-voltage photo taken July 7th by Pentti Arpalahti of Helsinki, Finland, is a great example:

But why? What makes these clouds of frosted meteor smoke the color of an electric discharge? It turns out, electricity has nothing to do with it.

NLCs are blue for two reasons: (1) The clouds consist of tiny ice crystals about the size of particles in cigarette smoke. Cigarette smoke looks blue, too, and for the same reason. Tiny particles scatter blue light better than other colors. (2) Ozone! Research in the 1970s revealed that some of the sunlight hitting noctilucent clouds first passes through Earth’s ozone layer. Ozone tends to scatter red light, while allowing blue to pass. Sunbeams hitting noctilucent clouds have thus been pre-conditioned for blue.



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Tom Halla

I’m probably too far south to see the noctilucent clouds at due west of Austin. TX. The pictures are stiking.


Yep. Toronto Canada is barely far enough north. link The vast majority of North Americans won’t be able to see this phenomenon.

The same thing happens in the southern hemisphere but almost nobody lives where it can be seen.


Why in summer is so much water vapor in the mesosphere?

Michael burns

The relationship between noctilucent clouds and SRM (Solar Radiation Management) is an interesting study to say the least.
I watched it last night…


Hey gusy, you missed to most important part of the NASA video ! They explain that it’s all due to …. you guessed it: CLIMATE CHANGE.

Methane gets oxidised to water vapour, and more human activity means more methane !
So we are very lucky to have another “canary in the coal mine.”

They don’t explain why you have to go down “complex” set of reactions to oxidise methane in order to find water on planet Earth.But hey, if they just wanted money to stare at clouds not much chance. If you can say it is a clever way to monitor climate change BINGO! Please give generously.


It is reportedly due to more methane in the upper atmosphere that combines with oxygen to form ice. Extra CO2 in the upper atmosphere also aids the process as it increases heat loss and cools in the 80+km region.

To conclude it is due to climate change requires proving a connection between increased methane and increased CO2 in the atmosphere being related to climate. Increasing CO2 has been linked to burning fossil fuels and increase methane is due to leakage of natural gas. Both increases are reportedly related to human activities not climate change.

A more appropriate conclusion is that it is a visible indication of rising CO2 and methane in the upper atmosphere – providing the proposed mechanism for ice formation at that altitude is correct.


I imagine that there are also H2O molecules released upon entry by meteors composed of hydrates as exhibited in chondrites.


But wait. Weren’t the liberal/socialist/communist/leftist/marxist/maoist/leninist/stalinist/social-injustice/regressive/eco-loon/police-state kooks saying earlier that these clouds were caused by Gore-bull warming? I swear they were…..


Forgot one :
There they say methane from farming. That would be the /Royal fruitcake/ category.
They do concede a solar cycle correlation though.


click on the NASA video .

Gunga Din

It was Hollywood.


It should be noted that these ice crystals started life as evaporated water with some 680 Watthrs of latent heat under the belt of each kilogram. And here they are some 80 kilometres high dissipating such heat as they still have into space.

I wonder what CO2 has to say about that.

It is a good thing that our gravity grabs them and brings them back to earth so they can do it all over again in a never ending cycle. Otherwise we would have lost our water many moons ago.


The water crystals that cause noctilucent clouds started life as methane in the stratosphere which was photo-dissociated to form water.

Loren Wilson

At 2 ppm in the atmosphere (lower atmosphere, presumably less as the height increases due to reaction) is there enough methane to do this? The volumetric concentration of methane at sea level assuming 2 ppm is 8.3 E-5 moles per cubic meter. At 80,000 meters, the density of air is 1.6 E-5 (16 millionths) the density at sea level. This means the concentration of methane in moles per cubic meter is now 1.4 E-9 moles per cubic meter. If we react all of the methane to water and CO2, we get 2.8 E-9 moles of water per cubic meter, or 5.0 E-8 grams per cubic meter. Ice only forms when the air becomes saturated with water. The vapor pressure of ice at this temperature is 5.7 E-3 Pa. Therefore, its saturated concentration is simply its vapor pressure divided by the absolute pressure = 5.7E-3/1.04 = 0.0055. It therefore takes 6.8 E-5 grams of water per cubic meter to form ice, and we don’t have enough methane to get there by a factor of 1000. I question their presumed source of water vapor, because it is theoretically impossible for it to come from atmospheric methane. Spreadsheet with calcs is available but I don’t know how to post it.


Thanks for that Loren. A bit above my pay grade but v. interesting. Again I note that the forming of ice crystals by whatever means, means that energy is being dissipated into space and also that these crystals eventually return to earth to be recycled. The cycle, of course, being the Rankine Cycle; enabled by water being lighter than dry air in the gaseous form; but heavier when formed into ice or liquid. A very efficient way of cooling the planet.
My regards


In the upper stratosphere about half of the water entered through the tropopause and half formed from methane. The noctilucent clouds only form in the coldest part of the atmosphere (the mesospause) and at the coldest part of the year (the Northern summer) and can be lower than 130K.

Bloke down the pub

Shouldn’t be any low level cloud getting in the way tonight so, here’s hoping.




Interesting!! I was always led to believe that NLC’s weren’t recorded prior to the eruption of Krakatoa in 1883. This due to volcanic dust being thrown violently very high up into the atmosphere and acting as aerosols for ice crystals to form.


Krakatoa had much of the world population staring at the skies every night. As the volcanic show subsided they probably were much more attuned than before. Also ind. rev. meaning more people were not slaves to the land who returned inside to eat as soon as the dusk stopped them working.

This may be a social change not a climatic one.


Yes, a very good couple of points.


Is ozone in the tropopause affects the escape of water vapor into the stratosphere?

Michael burns

What ozone…does it still exist. Cosmic ray is down so low, that the creation of new ozone lags the destruction.


In satellite imagery, Stratospheric Intrusions are identified by very low moisture levels in the water vapor channels (6.2, 6.5, and 6.9 micron). Along with the dry air, Stratospheric Intrusions bring high amounts of ozone into the tropospheric column and possibly near the surface.


I thought ozone was created by UV from the sun.


It is

Mike M

Oops! … another negative feedback.


how do you asses the climatic effect of these high level nocturnal clouds?

Keith R Jurena

Mesospheric weather is a form of heat rejection to deep space.

J Mac

Very Cool!

Charlie Adamson

Well that didn’t take long. It wasn’t long into the NASA YouTube video before they reflexively name dropped “climate change”. This time it’s that other spooky molecule METHANE! OOH! Be afraid,.. be very afraid! And we find it interesting to our agenda, so send us lots of money. Now they use methane and __a very complicated series of reactions__, as the source of the water at such high altitudes.

I have witnessed this sort of behavior throughout my life, but it became really common when I was introduced to governmental research programs for rocket development, nuclear reactor research, coal-gasification research. Despite being very disturbing the first time I observed people conflating their research results with other research (effectively drowning any new insight or discovery that may possibly be discovered on new adventures), the behavior kept showing up in program after program and became outright repulsive to me. This behavior proved the old saying: “Twenty years of experience,.. some people have twenty years of experience,.. growing with each new year, while others repeat their first year of experience twenty times.”

This once again leaves me with a profound sadness. All this potential talent swallowed up by malignant political plans. Mankind has yet to understand the full power of awareness and inquiry, of which science is but a tiny part playing a small role in our attempt at alleviating the suffering we all face.

Once again I give thanks for WUWT , Anthony, and everyone who keep the spirit of inquiry alive on this site. You are all a balm for my soul.

Alan Tomalty

Do these clouds act like other clouds do? Prevent some solar insolation and prevent some IR from escaping. Thus temperatures in troposphere rise?


These clouds reflect solar radiation, thus cooling the troposphere.

Peta of Newark

Ain’t that odd – ozone scatters red while oxygen scatters blue = Rayleigh Scattering and hence why the daytime sky is blue. Shouldn’t the night time sky thus be red?
And I thought ozone was ‘just everywhere’ and not in a nice cosy ‘layer’

I am soooo sure that impacts GHGE theory – what does CO2 do if not scatter infra-red?

Never mind that now, them sneaky little meotors have got into the water. In Wales.


“Ain’t that odd – ozone scatters red while oxygen scatters blue”

“Ozone tends to scatter red light, while allowing blue to PASS. “

Alan Tomalty

Here is a quote from the NASA website which is not true.

“But what makes carbon dioxide so interesting is that the gas absorbs energy in some small segments of the thermal infrared spectrum that water vapor misses. ”

Their very own graph on the same page says they are lying. Even at 13-18 micron water vapour is not a poor cousin as you can see. The key word is “misses”.

On a related topic regarding NASA , it is interesting that the findings of Richard Lindzen about the “iris” effect are so strong and so important to the destruction of the global warming theory that even NASA devotes a whole page to it. They say that one futher study confirmed the Iris effect and another debunked it. This is scandalous. Obvviously NASA are so scared of this finding that they couldnt outright debunk it since another study confirmed it. So for now the theory remains in limbo as a possible devastation of the greenhouse meme. What NASA should be doing is funding other studies with different scientists on each side of the argument to nail this down. Because NASA are not doing this, Gavin Schmidt knows that the IRIS effect kills the global warming hypothesis.

What is the IRIS effect you ask? Quoting from the very same NASA page.

““We wanted to see if the amount of cirrus associated with a given unit of cumulus varied systematically with changes in sea surface temperature,” Lindzen says. “The answer we found was, yes, the amount of cirrus associated with a given unit of cumulus goes down significantly with increases in sea surface temperature in a cloudy region.””

“This is the finding that led Lindzen’s team to propose that the Earth has an adaptive infrared iris—a built in “check-and-balance” mechanism that effectively counters global warming (Lindzen et al. 2001). Much like the iris in a human eye contracts to allow less light to pass through the pupil in a brightly lit environment, Lindzen suggests that the area covered by high cirrus clouds contracts to allow more heat to escape into outer space from a very warm environment.”

THE FACT THAT NASA WOULD EVEN ENTERTAIN DISCUSSION OF THIS ON THEIR WEBPAGE SHOWS THAT THEY ARE SCARED AS HELL OF THIS BEING TRUE. I will quote Dr. Lindzen himself on this topic in a report that he wrote for a conference that took place in August 2008 in San Marino.

“The paper received an unusually intense
review from four reviewers. Once the paper appeared, the peer review editor of the Bulletin of
the American Meteorological Society, Irwin Abrams, was replaced by a new editor, Jeffrey
Rosenfeld (holding the newly created position of Editor in Chief), and the new editor almost
immediately accepted a paper criticizing our paper (Hartmann and Michelsen, 2002), publishing
it as a separate paper rather than a response to our paper (which would have been the usual and
appropriate procedure). In the usual procedure, the original authors are permitted to respond in
the same issue. In the present case, the response was delayed by several months. Moreover, the
new editor chose to label the criticism as follows: “Careful analysis of data reveals no shrinkage
of tropical cloud anvil area with increasing SST.” In fact, this criticism was easily dismissed.
The claim of Hartmann and Michelsen was that the effect we observed was due to the intrusion
of midlatitude non-convective clouds into the tropics. If this were true, then the effect should
have diminished as one restricted observations more closely to the equator, but as we showed
(Lindzen, Chou and Hou, 2002), exactly the opposite was found. There were also separately
published papers (again violating normal protocols allowing for immediate response) by Lin et
al, 2002 and Fu, Baker and Hartmann, 2002, that criticized our paper by claiming that since the
instruments on the geostationary satellite could not see the thin stratiform clouds that formed the
tails of the clouds we could see, that we were not entitled to assume that the tails existed.
Without the tails, the radiative impact of the clouds would be primarily in the visible where the
behavior we observed would lead to a positive feedback; with the tails the effect is a negative
feedback. The tails had long been observed, and the notion that they abruptly disappeared when
not observed by an insufficiently sensitive sensor was absurd on the face of it, and the use of
better instruments by Choi and Ho (2006, 2008) confirmed the robustness of the tails and the
strong dominance of the infrared impact. However, as we have already seen, virtually any
mention of the iris effect tends to be accompanied with a reference to the criticisms, a claim that
the theory is ‘discredited,’ and absolutely no mention of the responses. This is even required of
papers that are actually supporting the iris effect.”


Alan Tomalty

Here is a more up to date quote from Dr. Lindzen. from 2017

“The energy budget of this system involves the absorption and reemission of about 200 watts per square meter. Doubling CO2 involves a 2% perturbation to this budget. So do minor changes in clouds and other features, and such changes are common. In this complex multifactor system, what is the likelihood of the climate (which, itself, consists in many variables and not just globally averaged temperature anomaly) is controlled by this 2% perturbation in a single variable? Believing this is pretty close to believing in magic.”


Here is a quote from the NASA website which is not true.

“But what makes carbon dioxide so interesting is that the gas absorbs energy in some small segments of the thermal infrared spectrum that water vapor misses. ”

Their very own graph on the same page says they are lying. Even at 13-18 micron water vapour is not a poor cousin as you can see. The key word is “misses”.

The quote is correct the spectra are line spectra and the H2O lines are fairly sparse whereas the CO2 lines are more numerous and do not coincide with the H2O lines. The spectra shown is low resolution and doesn’t show the lines individually.
This is a higher resolution CO2 spectrum:


Pathfinder pictures of Mars NLC’s –
I wonder if we have somewhere more Mars NLC data. Are they more frequent or more widespread?
ISS observations abound.
Very active structure with Lidar.

from :

1 Overturning assumptions about the sun and noctilucent clouds: Observations from the 1980s and ’90s suggested that the appearance of noctilucent clouds is linked to the sun’s activity, which rises and falls in about 11-year patterns. But AIM’s data tell a different story: noctilucent clouds have been steadily increasing over the past decade, despite the sun’s regular changes in activity. The precise reason for this is still unknown.

2 Noctilucent cloud and greenhouse gases: Scientists suspected that increased sightings of noctilucent clouds could be related to increasing greenhouse gases. Combining AIM’s data with 36 years of measurements from satellite instruments showed a correlation between more frequent noctilucent clouds and increases in water vapor, a greenhouse gas, and decreasing upper-atmosphere temperatures — a side effect of warming near the surface.


As the temperature in the lower stratosphere increases, water vapor can pass through the tropopause barrier.
comment image

Temperature of the lower stratosphere is flat.
comment image


Not above the 60th parallel, as shown in the graphics above.
It changes depending on the season. You only show anomalies.


I saw them on the 4th in eastern WA. So did relatives in NE Oregon.


I first saw them in southeastern Washington State 3 or 4 years ago.


The aliens are coming for the vineyards first.

Wayne Townsend

My wife just called these “contrails for the cosmos”. I suppose you could also say “Cosmic Contrails”. I can’t wait for the conspiracy theorists to start worrying about ET poisoning us.


Space alien chemtrails covered up by the US government!

An interesting review, but when they worked in methane and climate change, I hit the stop button.
Water vapour is in the atmosphere and the story did not require any stuff about converting methane to H2O.
Bob Hoye

I’m told that when watching a tropical sunset for the “Green flash” it helps to have a few gins and tonic.
What is recommended for meteor smoke?
Bob Hoye


Ganja ??


figured it had to be tied into global warming and needing more research to study, i.e. more grant money.